Growth hormone therapy and related methods and pharmaceutical compositions

ABSTRACT

Human growth hormone therapy and thymic regeneration are effected by the generally simultaneous administration of one of human growth hormone, its analogs, precursors, metabolites, releasers or mixtures thereof in combination with one of DHEA, its precursors, releasers, analogs, metabolites or combinations thereof.

BACKGROUND OF THE INVENTION

The present invention relates to human growth hormone therapy and to thecure of human disease through organ and tissue transplantation. Thepresent invention includes a method for regenerating the human thymus toallow intrathyric transplantation and thereby the elimination of organand tissue rejection. There are two variations of this method, one thatemploys growth hormone and one that employs agents that can substitutefor growth hormone's thymus-regenerating effects. The former method haswide applicability beyond the transplantation of tissues and organs,because it involves the elimination of the most important side effectsof growth hormone. Human growth hormone (HGH) has been recognized as atreatment for children of short stature or with renal failure, and hasbeen a safe and effective treatment in most cases, but there are severalreports that such children often experience hyperinsulinemia as a resultof HGH administration. Further, HGH has been considered as a powerfulapproach to the treatment of human aging, but its widespread use isinhibited by its serious side effects, the most important of which iselevation of fasting and glucose-stimulated insulin levels, a phenomenonthat is known to be a risk factor for atherosclerosis and cardiovasculardisease. Arginine, an HGH releaser, has therapeutic effects in its ownright, but has the same drawback of elevating blood insulin levels. Theinvention described here permits HGH therapy to be administered with noelevation in blood levels of insulin.

Much has been written of late about the growing excitement of anti-aging(gerolytic) therapies, including hormone replacement therapy withdehydroepiandrosterone (DHEA), melatonin, sex hormones, thyroid hormone,cortisol, or human growth hormone. Of these, the work of Rudman hasattracted the most attention because of his statement thatadministration of human growth hormone (HGH) produced the same effectsas the reversal of 20 years of aging. Rudman and others have, in fact,amassed an impressive body of evidence indicating that it is the loss ofHGH with age that is responsible for much of the human aging process,including atrophy of internal body organs, thinning of the skin, slowingof cell division, weakening of muscles and bones, and accumulation ofbody fat. Even immune system decline with age seems largely dependent onloss of HGH. Furthermore, GH administration to animals produces aradical increase in longevity.

On the other hand, Marcus et al. have shown the down side of HGH: givenat the minimum doses used in Marcus' study, equivalent to the doses usedby Rudman, HGH produced dramatic and disturbing rises in fasting andstimulated serum insulin levels. The administration of HGH is known todecrease the body's sensitivity (i.e., responsiveness) to insulin, thuscausing a compensating rise in pancreatic insulin output and thereforein serum insulin levels; yet paradoxically, falling HGH levels in aginghumans are accompanied by increasing serum insulin levels.

Elevated insulin, in turn, has been linked in many studies and via manymechanisms to the development of atherosclerosis, hypertension, andheart disease. It is absolutely a major factor holding back thewidespread clinical application of HGH for combatting many of themaladies of aging, dimming the attraction of this otherwise spectacularanti-aging intervention. HGH also leads to mild rises in serumcholesterol and triglycerides, raises blood pressure, and may producesymptoms similar to arthritis.

Of all the developments in modern immunology that promise to make therejection of transplanted cells, tissues, and organs obsolete, the mostexciting is the technique of intrathymic transplantation pioneered byNaji et al. This is so because the method requires no specific attentionto the details of the rejection process, can be applied to thetransplantation of virtually any tissue or organ into virtually anyrecipient, probably including even transplantation between unrelatedspecies, without complex tailor-made immunopharmaceuticals, and withminimal trauma to the recipient, and can reverse established autoimmunedisorders including autoimmune diabetes. The method involves firsttransplanting a biopsy sample of the graft into the thymus of therecipient and then transplanting the graft itself after a predeterminedtime. The presence of the intrathymic biopsy renders the host tolerantto the graft itself, either by eliminating or anergizing immune cellsthat attack the biopsy in the thymus. In addition, it is likely that, inthe case of autoimmunity, the host can be made tolerant of its owntissue again by transplanting it into the thymus, thus reversingautoimmunity. Contrary to the presumption that tolerization will requirea longer time than the ex vivo lifetime of the graft to be transplanted,recent studies have shown that success can be achieved when kidneys aretransplanted into the recipient within 24 hours of the time the renalbiopsy is placed into the recipient's thymus. Rejection is suppressed inthe short run by a single dose of antilymphocyte globulin and/or byother conventional immunosuppression until tolerization makes furtherimmunosuppression unnecessary. Bone marrow transplantation is alsobelieved to induce tolerance to subsequent grafts from the same donor bythe migration of bone marrow cells into the thymus, an equivalentprocess to transplantation of actual organ tissue samples in the thymus.

The main problem with this method is that it requires a functioningthymus gland of significant mass in order to be effective. The humanthymus begins to involute before the age of 20 and becomes severelyatrophied by the age of 40, and transplant surgeons and immunologistsare at a loss for a way of overcoming this problem. In fact, it isthought that age-related thymic involution accounts for a major part ofage-related morbidity and mortality and therefore represents a majorunsolved health problem worthy of solution in its own right.

What has not been recognized by the medical community is that thymicregeneration is possible in humans. Many animal studies attest to thefeasibility of thymic regeneration in animals using several differentmethods. Several human studies have shown that immune system functioncan be restored in older humans, but it has never been suggested thatthis is due to thymic regeneration. The present invention effects thymicregeneration in man.

Several methods have been shown capable of reversing thymic involutionin animals and, by inference, in man, but none are feasible for humanuse. Administering a male contraceptive to rats results in dramaticthymic regeneration, but would not be desirable in humans for a varietyof reasons, including major testicalar shrinkage. It has been recognizedthat hyperthyroid humans do not undergo age-related thymic involution,and that administration of thyroid hormone to older humans results in arestoration of youthful indices of immune system function, butadministration of thyroid hormone is considered hazardous, andhyperthyroid individuals have a number of medical problems. The problemsof regenerating the thymus of diabetic animals or humans have not beenconsidered at all in the prior art.

As noted above, the use of growth hormone alone for this purpose wouldbe contraindicated by the adverse effect of growth hormone on insulinsensitivity, despite the ability of growth hormone to regenerate thethymus in rodents and dogs and to improve immunity in older humans.Growth hormone use for thymic regeneration could lead to unacceptableloss of control of insulin responsiveness in diabetics and elevatedinsulin levels in non diabetics. In fact, since elevated insulin leadsto virtually all of the side effects of growth hormone (hypertension,atherosclerosis, water retention, and cardiovascular morbidity), it ispossible that most of these side effects are a result, at least in part,of the elevation of insulin produced by growth hormone.

SUMMARY OF THE INVENTION

In the present invention, it has been surprisingly discovered that onecan increase a patient's level of human growth hormone without causing acorresponding increase in serum insulin levels by administering eitherhuman growth hormone (HGH) or its equivalent (active HGH analog, HGHmetabolite or fragment, HGH mimic, HGH releaser or mixtures thereof) incombination with dehydroepiandrosterone (DHEA) or its equivalent(DHEA-sulfate, other DHEA precursor, DHEA releaser, DHEA metabolite(s),DHEA equivalent analog, or mixtures thereof). (Here we define a “mimic”as a structurally dissimilar compound that has the same biologic actionas the natural biological molecule.) This is surprising, in that humandata militate against an insulin-suppressing effect of DHEA in normalpeople, and suggest that DREA administration can actually elevateinsulin levels indirectly.

In another aspect of the invention, it has been surprisingly determinedthat in addition to effecting other positive results associated withhuman growth hormone treatment, the above regimen can permit the cure ofdiabetes and a range of other diseases by actually regenerating thehuman thymus and thereby allowing subsequent intrathymictransplantation.

These and other objects, advantages and features of the presentinvention will be more fully understood and appreciated by reference tothe appended specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 charts serum fasting glucose and fasting insulin levels againstserum DHEA-sulfate levels in an arginine (HGH releaser) administrationexperiment involving DHEA administration;

FIG. 2 charts the relative change in insulin level against the relativechange in serum DHEA-sulfate level in the same experiment as FIG. 1;

FIG. 3 graphs DHEA serum concentration against serum concentration forDHEA-sulfate;

FIG. 4 compares the correlation between insulin level and either DHEAconcentration or testosterone concentration;

FIG. 5 charts the blood serum level of IGF-1 against time in an arginineand DHEA administration experiment;

FIG. 6 charts serum insulin, IGF-1 and DHEA against time, during aprotocol involving administration of HGH and DHEA.

DESCRIPTION OF THE PREFERRED EMBODIMENTS General Procedure

In the preferred embodiment, human growth hormone (HGH) or itsequivalent analog, metabolite, fragment, releaser, mimic, or mixturethereof is administered by subcutaneous injection or other efficaciousroute every day or every other day or three times a week (e.g., Monday,Wednesday and Friday) at an HGH equivalent dose of 0.01 to 0.05 mg/kg ofbody weight, the dose being adjusted to avoid peak levels of growthhormone or somatomedin C greater than those found in individuals thatare 10-30 years of age. (Peak levels similar to those 10-20 years of ageare appropriate for thymic regeneration; levels similar to those of20-30 year olds are appropriate for chronic growth hormone replacementtherapy.)

The most desirable target range for somatomedin C levels in men andwomen for long-term growth hormone replacement therapy is 700-3000units/L, and particularly 1000-1600 units/L (where 1 unit equals 150 ngof somatomedin C). For short-term thymus regeneration, the targetsomatomedin C levels are 700-7000 (most preferably 700-5000) units/L forwomen and 700-6000 (most preferably 700-3000) units/L for men.Simultaneously with or slightly before HGH administration, DHEA, DHEAprecursor (such as DHEA-S), DHEA releaser, equivalent metabolite,equivalent DHEA analog or a mixture thereof is given orally or viaanother efficacious route at a DHEA equivalent dose of 50-2000 mg, morepreferably 50-1000 mg/day, the dose being adjusted based on thecirculating DHEA level (not to exceed levels found in individuals 20-25years of age by more than 100%) and the response of circulating insulinlevels (insulin levels should be adjusted by DHEA dose until they are ator below the pre-HGH insulin basal levels). The most desirable targetrange for circulating DHEA is 300-800 ng/dl. This regimen should becontinued preferably for 1-3 months before intrathymic transplantation,and/or indefinitely for applications related to aging or growth.

The term HGH is intended to include recombinant or natural human growthhormone. HGH releasers are compounds which stimulate the body'sproduction and/or release of HGH and include, but are not limited to,growth hormone releasing hormone (GHRH), clonidine, phenylalanine,L-DOPA, arginine, ornithine, deprenyl, and somatostatin inhibitors. HGHwill be effective whether it is supplied exogenously or released fromthe pituitary by such releasing agents. Consequently, the use of agrowth hormone releaser is an acceptable variation on the use of growthhormone itself, in those patients who are able to release adequategrowth hormone in response to such agents. Patients who are able torelease appreciable but not sufficient HGH in response to such agentsmay be given both a releasing agent and exogenous HGH so as to attainthe required HGH levels for thymic regeneration while minimizing the useof exogenous HGH, which is expected to be more expensive than HGHreleasers. Furthermore, the entire HGH molecule may not be required forHGH action. Therefore, equivalent analogs such as genetically-engineeredvariants or fragments of HGH that retain the biological activity of HGHbut that are less expensive or have fewer side effects are alsoacceptable variations. The dosage for any of these HGH alternatives are“HGH equivalent doses,” that is they should yield the same desired levelof or effect of HGH in the body. An example of an HGH “mimic” would besomatomedin C. The best mode process is also compatible withadministration of drugs that block other side affects of HGH, e.g.,parlodel to block gynecomastia in men.

DHEA should be given “to effect.” “To effect” is defined as sufficientto lower that particular patient's insulin levels down to either basallevels or, if basal levels are elevated in comparison to an acceptedstandard for good health and long life, to levels deemed to maximizelongevity and health. Typically, this will involve most preferably DHEAdoses of 50-1000 mg/day, a range considerably below the “overkill” dosesof 1600 to 2500 mg/day being employed routinely in human clinicaltrials, which maximize the danger of complications such asmasculinization of women or worsening of benign prostatic hypertrophy inmen. All routes of administration fall within the limits of the bestmode process, and the substitution of any DHEA precursor, releaser (suchas an enzyme that cleaves DHEA-S to “release” DHEA), equivalent DHEAmetabolite or equivalent analog of DHEA that has the sameinsulin-suppressing role as DHEA itself constitutes an acceptablevariation, including combinations of DHEA and agents that block anyundesired effects of DHEA.

DHEA-sulfate is an example of a DHEA precursor. Although DHEA isconsidered to be active and DHEA-sulfate to be inactive, tissue enzymesexist that convert DHEA-sulfate into DHEA in the body. Consequently,DHEA-sulfate rather than DHEA itself may be administered in a doseappropriate to raise DHEA levels to insulin-suppressing values (or toproduce similar insulin suppression directly). The term DHEA releaser isintended to include any other compound which causes the body to produceor release DHEA in the body. The dosage required for any of thealternatives to DHEA per se should be “DHEA equivalent doses,” that is,doses that yield the same insulin lowering effect as the indicated dosesof DHEA.

The precise mechanism of operation of the preferred embodiment is notknown. DHEA does not simply eliminate excess insulin, and indeed thatwould be undesirable, since the increased insulin level is in responseto the body's reduced insulin sensitivity. Rather, DHEA apparentlydirectly counters the desensitizing effects of HGH, thus allowing thebody to obtain the same glucose uptake with lower, indeed normal,insulin levels.

Adding DHEA to counter the insulin-raising effects of growth hormone iscompatible with the use of any drugs that may be developed that limitthe conversion of DHEA to masculinizing androgens in either women or menor otherwise suppress DHEA or DHEA-sulfate side effects. The optimumdose of DHEA is that dose that successfully suppresses insulin to thedesired level and maximizes subsidiary benefits such as inhibition ofatherosclerosis without producing side effects.

The time of DHEA administration is optimally close to the time ofadministration of HGH so that DHEA will be present in the blood streamwhen the insulin-elevating tendency of HGH is maximal. For example, oralarginine taken just before bedtime should be accompanied by DHEA. Apharmaceutical agent consisting of HGH+DHEA or HGH releaser +DHEA or HGHanalog +DHEA or any of these HGH variants +DHEA analogs or DHEA-sulfate,etc., would embody this best mode approach. However, the process ofusing DHEA to suppress insulin includes administration at other times aswell. The effects of HGH on human physiology last approximately sixmonths or more. Consequently, administration of DHEA or its equivalentto suppress insulin elevated by previous HGH administration or itsequivalent is valid at any time insulin is elevated by prior HGH or HGHequivalent administration.

EXPERIMENTAL RESULTS Experiment 1 Administration of Arginine (an HGHReleaser) and DHEA

A human patient was placed on a standardized regimen of nutrient intakefor two weeks to establish a baseline prior to ingesting any HGHreleasing agents. The evening prior to blood analysis, the same eveningmeal was consumed (salnon, potato, white wine, vegetables, and Caesarsalad). Upon establishing basal values for glucose, insulin, somatomedinC (a marker for growth hormone), DHEA-sulfate, serum lipids, andtestosterone, a daily regimen of ingesting 15 grams of arginine justbefore bedtime was instituted. This regimen was maintained for one week,after which a new baseline was obtained. The evening following this newbaseline measurement, DHEA was ingested at a dose of 180 mg (two 90 mgcapsules taken simultaneously) at the same time as the arginine. Thiswas continued for one week and the baseline levels of metabolites wererechecked. Finally, for the last week, the arginine dose wasadministered every other day or at 7.5 g/day while DHEA levels weremaintained. Thus, the data points are as follows:

1: Baseline—begin 15 gm/day administration of arginine;

2: Day 7—begin 180 mg/day DHEA;

3: Day 14—begin 15 gm arginine every other day or 7.5 g/day; and

4: Day 21—end of experiment, no arginine administered the previousnight.

The primary results are given in FIG. 1 and FIG. 2, which document thechanges in insulin and glucose levels that accompanied the introductionand tapering off of arginine administration and their relationship toDUEA (reflected in FIG. 1 by DHEA-sulfate due to a missing basal valuefor DHEA itself). There was no change in glucose concentration, which isconsistent with the known lack of effect of HGH on glucoseconcentrations. On the other hand, fasting serum insulin rose nearly 50%in response to arginine ingestion (point 2), but was brought down toonly 76% of basal levels by the ingestion of DHEA, despite thecontinuing and undiminished administration of arginine (point 3). Thisdata point thus provides the crucial validation of the hypothesis andthe key to removing the side effects of HGH administration. Point 4gives the result of dropping arginine administration to a regimen ofevery other day ingestion, no ingestion having taken place the nightprior to the blood analysis represented. Here insulin has returned tobasal levels. The significance of this point is that it shows thecombination of HGH release and DHEA administration regimens thatprecisely balances the effects of these two hormones on insulin levels.

There are two other aspects of FIGS. 1 and 2 that seem significant.First, accompanying the elevation of insulin that results from arginineingestion (point 2 versus point 1) is a noticeable increase inDHEA-sulfate. This is an endogenous increase, since no DHEA was ingestedover this period, and establishes a putative link between the release ofHGH and DHEA. This link is confirmed by comparing points 3 and 4, whichshow that, with no drop in DHEA ingestion, the circulating level ofDHEA-sulfate fell in response to the fall in arginine ingestion. Fromthese results, it would appear that DHEA levels are normally modulatedby growth hormone so as to buffer the effects of growth hormone oninsulin. This is consistent with animal studies showing a DHEA-releasingeffect of growth hormone. With aging, DHEA levels become insufficient tocarry out this function, since DHEA falls faster with age than does HGH,and a rise in insulin is thus expected.

FIG. 3 shows the correlation between DHEA-sulfate and DHEA in thisstudy. The correlation appears adequate to use in assuming that theDHEA-sulfate levels shown in FIG. 1 reflect DHEA levels.

FIG. 4 presents evidence that the effect of DHEA is due to DHEA itselfrather than testosterone, which rises upon DHEA administration and hasbeen linked to insulin sensitivity in women with polycystic ovariansyndrome. FIG. 4 shows that the correlation between insulin and DHEA isfar better than the correlation between insulin and testosterone,contrary to previous results with these women. (Lines are least squaresregression fits.)

FIG. 5 shows a paradoxical result, namely, an actual DROP, as opposed tothe expected RISE, in somatomedin C (also known as IGF-1) levels inresponse to oral arginine. This drop was sustained as long as arginineadministration was continued. An independent experiment confined thisIGF-1-lowering effect of arginine: basal levels of 223 ng/ml fell to 166ng/ml two hours after arginine ingestion. Direct addition of arginine tothe serum sample to determine whether arginine interferes with thechemical assay for IGF-1 indicated that 4 mM arginine made IGF-1 levelsread higher than 1 mM arginine in the serum, not lower, arguing that theIGF-1-lowering effect is real, not artifactual. Others have alsomeasured somatomedin C levels following arginine ingestion or infusion,and found them to be depressed despite good release of HGH. There is noexplanation for this paradox, but it is not material to the fact thatHGH is released by arginine and that released HGH does elevate insulinand that DHEA does block this insulin-elevating effect.

Arginine is known to be a secretagogue for insulin in its own right, andthe possibility that it could be responsible for a major part of theinsulin elevation observed must be considered. However, this possibilityappears unlikely for the following reasons. First, the time course ofinsulin elevation in humans following arginine ingestion or infusion israpid: insulin levels peak in about 30 minutes or less and fall back tobaseline within 1-2 hours, whereas in the experiment reported in FIG. 1,insulin was measured 11-13 hours after arginine ingestion. Insulin atthat late time could only have been affected by long-term secondaryeffects of arginine ingestion, i.e., HGH release and its resultinginsulin elevation, which takes more than 6 hours to fully develop.Further, in the experiment described in FIG. 1, an insulin determinationafter only 3 days of arginine ingestion revealed a normal insulin level(data not shown in FIG. 1), indicating that it is not the acute anddirect insulin-releasing effect of arginine that is primarilyresponsible for the insulin elevation observed, but insulin resistancederived from delayed arginine-induced HGH release.

Experiment 2 Administration of HGH and DHEA

The above-described experiment is based on the generally acceptedassumption and observation that arginine activates the endogenousrelease of HGH. This second experiment was conducted to confirmcomparable results from the direct administration of HGH.

As in the first experiment, a standard dietary regimen was followed theevening before each blood sample was collected. HGH administration wasinitiated one day after a baseline blood sample was drawn. HGH wasinjected subcutaneously at a dose of approximately 0.018 mg/kg/day,every other night, and was injected near midnight prior to bloodcollection the following morning. Blood was collected between 10:30 and11:00 a.m. The second blood sample was taken on day 8, or just over 7days after beginning HGH injections (4 injections in total to thattime). After this second blood sample, a “wash out” period of two dayswas allowed prior to reinitiating injections according to the sameschedule. On day 9, during the HGH “wash out” period, a priming dose of200 mg of DHEA was taken in divided doses to prepare the patient for theHGH. The second round of injections was done simultaneously with theingestion of two 100 mg capsules of DHEA, beginning on the evening ofday 10. This regimen continued for a total of 4 HGH injections,culminating in the final injection on day 16 and blood sampling on day17. Two hundred mg of DHEA were taken also on the nights between HGHinjections, at the normal time. HGH injections were administered nearmidnight of the day stated.

The results of this experiment are shown in FIG. 6 and Table 1. Theeffects on insulin are virtually identical to those of the originalarginine experiment, insulin rising by 57% prior to DHEA ingestion andfalling to 101.5% of control levels after combining HGH with DHEA.Therefore, there is no doubt of the antihyperinsulinemic effect of DHEAin the presence of hyperinsulinemia-inducing doses of HGH, a phenomenonthat has never before been documented or suspected. Further, there is nodoubt that currently recommended doses of HGH do produce a serioushyperinsulinemic effect. HGH actually depressed circulating DHEA levelsby a third while leaving DHEA-sulfate unaltered; this is presumably amanifestation of the well-known DHEA-depressing effect of insulin, andis different from the net DHEA-sulfate-elevating effect, and apparentDHEA-elevating effect, of arginine administration documented above. Thismay reflect the depressed IGF-1 levels in the arginine protocol versusthe elevated IGF-1 levels with HGH administration, and is explicable ifIGF-1 (“insulin-like” growth factor) contributes to the suppression ofDHEA by a mechanism similar to that of insulin. Regardless, the largechange in DHEA level further supports functional interrelationshipsbetween HGH and DHEA. In fact, it is fascinating that DHEA appears togovern the differential effects of HGH on IGF-1 versus insulin, allowingIGF-1 to rise with HGH administration (desirable) while insulin remainsunchanged (desirable) despite the similarities of the two. The exactdata for all metabolites measured are reported in Table 1.

TABLE 1 Level Stage of HGH + Metabolite Experiment: Baseline HGH onlyDHEA Insulin (uU/ml) 6.6 10.4 6.7 IGF-1 (ug/dl) 27.0 35.5 37.1 DHEA(ng/dl) 360 240 530 DHEA-sulfate (ug/dl) 146 146 688

Direct Applications of DHEA and HGH Co administration

Some obvious implications of the successful reversal of the mosttroubling side effect of HGH administration, the rise in serum insulinand the fall in insulin sensitivity, are (a) the ability to use HGH inmany more normal individuals for the direct treatment of aging withminimal fear of side effects, (b) the ability to use HGH in olderdiabetics, whose need for HGH probably exceeds that of normal elderlyindividuals but whose ability to take HGH would be ruled out by mostphysicians in the absence of a means of normalizing insulin sensitivity,and (c) the ability to use HGH to treat younger people suffering fromboth pituitary insufficiency and adrenal insufficiency. The combinationof DHEA and arginine may also be useful when arginine is used in dosesbelow the HGH-releasing dose to stimulate immunity or when arginine isused as a laxative or for other purposes. The applications mentionedalso pertain to the physiological equivalents of HGH+DHEA.

Curing Diabetes With HGH and DHEA Coadministration

A nonobvious application is to cure diseases such as diabetes. The keyto this application is the ability to use DHEA+HGH to regenerate thehuman thymus. Most age-related immune system decline is caused by thymicinvolution (atrophy). Thymic involution is not now a clinicallytreatable condition, and it affects virtually 100% of the adultpopulation. The concurrent administration of human growth hormone or anHGH releaser and DHEA, its metabolites or equivalent analogssurprisingly reverses thymic involution in older individuals and inothers with thymic insufficiency.

By regenerating the previously atrophied thymus, this coadministrationof HGH and DHEA allows intrathymic transplantation in elderly orinvoluted individuals as a route to permanent grafting of tissues andorgans without immunosuppression and without rejection, a technique notformerly applicable to those over the age of 30-40 or to those patientswith atrophied thymuses (e.g., hypothyroid patients). Three immediateapplications of this method are the cure of insulin dependent diabetes,the reversal of autoimmune conditions in those over 30, and theengrafting of older individuals with organs or with geneticallyengineered cells and tissues from unrelated sources without rejectionand without chronic immunosuppression.

The regimen for administering human growth hormone and DHEA or theirequivalents for the rejuvenation of the thymus is as described above inthe preferred embodiment. The regimen should be continued preferably for1-3 months. For best results, this regimen can be supplemented withother immune-system strengthening agents, particularly coenzyme Q₁₀(10-200 mg/day), Vitamin E (200-1000 IU/day) and zinc (30-100 mg/day).Further, chromium picolinate (100-1000 micrograms/day) may be used tosupplement DHEA/DHEA-sulfate.

After thymic regeneration, the thymus should be imaged (preferably bymagnetic resonance imaging, though other methods are also acceptable) toverify regeneration and thymic location. Surgery should then take placeon the same day as or the day after HGH and DHEA are administeredaccording to the protocol specified above. At this time, a surgeonskilled at thymic biopsy retrieval injects into the thymus anappropriate sample of the tissue or organ to be transplanted later, orinjects any other donor-specific cells or antigens (for example, bonemarrow cells) that are the immunological equivalent of the tissue itselfin stimulating deletion or anergy of the cells otherwise responsible forlater rejecting the transplanted tissue or organ. This tissue may be anendogenously-derived sample in the case of those with autoimmunediseases, e.g., myelin from the cauda equina to reverse multiplesclerosis; a joint biopsy to reverse autoimmune arthritis; or endogenousislets to reverse incipient diabetes in the case of diabetes that hasnot progressed to the point of major islet die-off. The amount ofinjected tissue is equivalent to {fraction (1/10)}th to twice the amountspecified by Naji's prior art for animals without thymic atrophy (basedon the ratio of thymic volume to volume of the injected tissue and/or onthe ratio of the volume of injected tissue to body weight). A variationon direct intrathymic injection is peripheral injection of cells thatspontaneously migrate to the regenerated thymus (e.g., bone marrowcells) and thus induce tolerance.

At the same time the intrathymic or peripheral injection is given, thepatient is given a standard dose of antilymphocyte globulin or otherappropriate immunosuppressant to ensure persistence of the intrathymicgraft until the recipient's immune system becomes tolerant of thedonor's tissues. The desired tissue or organ transplant itself may begiven on the same day as the intrathymic injection, accompanied bymaintenance immunosuppression until tolerance is attained, or thistransplantation may be delayed until tolerance is attained, in order toavoid the need for immunosuppression lasting longer than 1-2 weeks, orto avoid the need for higher doses of immunosuppressants.

In the case of curing diabetes, it is desirable to inject pancreaticislets into the thymus in order to be able to judge the “take” ofinjected material based on islet function and in order to attain somepreliminary minimal protection from diabetes prior to the subsequenttransplantation of islets by infusion into the portal vein or othersite.

In the case of reversing autoimmunity, the priming injection to thethymus need not be followed by further transplants unless an additionalintrathymic endogenous tissue sample is required to facilitate reversalof the autoimmune state. For such patients, anti-rejection medicationshould be used sparingly or not at all.

Alternative Embodiments for Thymic Regeneration

In broader aspects of thymic regeneration to facilitate thymic injectionand subsequent organ and tissue transplantation, alternative methods forregenerating the thymus can be utilized. First, insulin sensitizing (andtherefore lowering) agents other than DHEA and its above-describedrelatives can be employed in place of DHEA. Chromium picolinate andsimilar formulae involving chromium (such as “GTF” or glucose tolerancefactor preparations available in health food stores) and phenforminrepresent the only known members of this class of agents. As in the caseof DHEA, the appropriate dose is to be adjusted based on theinsulin-lowering response attained in a particular patient. Chromiumpicolinate is particularly exciting because of its low toxicity, itsability to extend the life span of animals by 50%, and because itsability to increase insulin sensitivity is a key anti-aging effect. Theaction of chromium picolinate is not considered to be similar to theactions of DHEA in humans in the prior art because the insulin-loweringeffect of DHEA is unknown in the prior art. Although the ability ofchromium picolinate to reverse GH-induced elevation of insulin levelshas been reported in passing in pigs, its use in regenerating the thymushas never been contemplated in the prior art, the further application ofthis regeneration to tissue and organ transplantation has similarlynever been previously contemplated, and its use in combination with HGHfor these ends has also not been contemplated in the prior art.

A last approach to regenerating the thymus is to use agents other thanthe equivalent of HGH and DHEA, whose thymus-regenerating effectsubstitutes for that of growth hormone but does not involve elevation ofinsulin levels. In particular, the use of zinc alone, Vitamin E alone,or coenzyme Q₁₀ alone have shown promise in restoring immune systemfunction in elderly animals and humans. The use of all three agentstogether provides an improved method of stimulating immunity that willregenerate the thymus sufficiently to permit subsequent intrathymictransplants without producing undesirable effects on insulinsensitivity. Consequently, a third choice for thymic regeneration is touse 30-130 mg/day of zinc plus 200-1000 IU/day of Vitamin E plus 10-200mg/day of coenzyme Q₁₀ for 1-3 months. This approach will be desirablewhen HGH and DHEA or their equivalents cannot be used for any reason.

Of course, it is understood that the foregoing are merely preferredembodiments of the invention and that various changes and alterationscan be made without departing from the spirit and broader aspectsthereof, as set forth in the appended claims.

What is claimed is:
 1. A method for treating autoimmune diseasescomprising: regenerating the patient's involuted thymus; and injectingendogenous material into the patient's thymus, the endogenous materialrepresenting the target of the autoimmune attack.
 2. The method of claim1 in which said endogenous material comprises pancreatic islets, wherebyautoimmune diabetes can be cured.
 3. The method of claim 1 in which saidendogenous material comprises myelin, cartilage, renal tissue or skin,whereby multiple sclerosis, arthritis, lupus erythematosus, andscleroderma can be cured.
 4. The method of claim 1 in which said step ofregenerating said patient's involuted thymus comprises: administering afirst compound selected from the group consisting of human growthhormone, human growth hormone analogs, human growth hormone precursors,human growth hormone metabolites and mixtures thereof, combined with theapproximately simultaneous administration of a second compound selectedfrom the group consisting of dehydroepiandrosterone,dehydroepiandrosterone precursors, dehydroepiandrosterone analogs,dehydroepiandrosterone metabolites, and combinations thereof.
 5. Themethod of claim 4 in which said endogenous material comprises pancreaticislets, whereby autoimmune diabetes can be cured.
 6. The method of claim4 in which said endogenous material comprises myelin, cartilage, renaltissue or skin, whereby multiple sclerosis, arthrits, lupuserythematosus, and scleroderma can be cured.
 7. A method for treatingautoimmune diseases comprising: regenerating the patient's involutedthymus; administering an immunosuppressant; and injecting material intothe patient's thymus, the material representing the target of theautoimmune attack; wherein said step of regenerating said patient'sinvoluted thymus includes administration of a first compound selectedfrom the group consisting of human growth hormone and functionallyequivalent human growth hormone precursors, human growth hormonemetabolites, human growth hormone analogs, and mixtures thereof, and theapproximately simultaneous administration of a second compound selectedfrom the group consisting of dehydroepiandrosterone and functionallyequivalent dehydroepiandrosterone precursors, dehydroepiandrosteronemetabolites, dehydroepiandrosterone analogs, and mixtures thereof.
 8. Amethod for treating autoimmune diseases comprising: regenerating thepatient's involuted thymus; and injecting material into the patient'sthymus, the material representing the target of the autoimmune attack;wherein said step of regenerating said patient's involuted thymusincludes administration of a first compound selected from the groupconsisting of human growth hormone and functionally equivalent humangrowth hormone precursors, human growth hormone metabolites, humangrowth hormone analogs, and mixtures thereof, and the approximatelysimultaneous administration of a second compound selected from the groupconsisting of dehydroepiandrosterone and functionally equivalentdehydroepiandrosterone precursors, dehydroepiandrosterone metabolites,dehydroepiandrosterone analogs, and mixtures thereof.